https://www.uab.edu/news/health/item/11082-investigational-c...
Discovering (100s of)compounds in a lab (which is what the public funds pay for) is the easy and much cheaper part.
Testing it in humans and modifying it for that purpose is hard, expensive, and time consuming. Pretending like these drug companies do nothing and just take all the benefit from public research is incorrect.
If you want a lot of drug research, you probably want to ensure that successful drug research is lucrative. (Maybe less than today, maybe making unsuccessful research or negative reproduction more lucrative than today.)
In fact, I’m pretty sure the taxpayers are subsidizing investors with all the free research and knowledge they get from taxpayer funded higher educational facilities.
Developing medicines is a high risk venture. But the rewards are extremely high also, so maybe it merits the resources of all of society. This is ignoring that US taxpayers already pay for a significant portion of the R&D via universities.
There is nothing to stop that under the current model. It just isn't happening.
Reforming the FDA process could save an large amount of lives and money.